JPS627972A - Starter with planetary reduction gear - Google Patents

Abstract

PURPOSE:To prevent seizure and excessive wear by forming unevenness at the outside surface of a planet gear supporting pin or the bore on the planet gear side, and by encapsulating lubricant there. CONSTITUTION:A groove 13 to form unevenness is provided at the outside surface 2a of a supporting pin 2 for a planet gear 1. The groove 13 is in communication with an oil hole leading from the end face 2b of this planet gear supporting pin 2 to its outside surface 2a. A transverse hole 14 and a longitudinal hole 15 in connection with this oil hole are filled with grease previously, which is fed little by little to the slide faces through the action of the centrifugal force generated under operation. This gives sufficient holding of lubricant at the slide faces of the outside surface of said planet gear supporting pin and the bore on the planet gear side to lead to prevention of seizure and excessive wear.

Description

Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to a planetary gear reduction type starter, and in particular, a lubricating oil film is provided on the sliding surface between the outer circumferential surface of a planetary gear support pin and the inner circumferential surface on the side of the planetary gear. This invention relates to a planetary gear reduction type starter suitable for forming.

[Background of the invention]

The conventional planetary tooth city reduction type starter is disclosed in Japanese Patent Application Laid-Open No. 59-221.
As described in Japanese Patent No. 463, a bearing such as a needle bearing is fixed to the inner diameter surface of the planetary gear by a press-fit cap, and is rotatably supported by a planetary gear support pin.

However, sufficient consideration has not been given to seizure and abnormal wear of the outer periphery of the planetary gear support pin, the inner periphery of the bearing on the planetary gear side, the inner periphery of the planetary gear, and the like.

The actual situation will be explained with reference to FIG.

FIG. 12 is a front sectional view of a general planetary gear reduction type starter.

In FIG. 12, 1 is a plurality of (for example, three) planetary gears, 2' is a planetary gear support pin fixed to the planetary arm 3 by a method such as press fitting, 4 is a starter motor, and 4a is an armature of the starter motor 4. The shaft, 5 is a central sun gear (hereinafter simply referred to as a sun gear) fixed to the armature shaft 4a, and 6 is an internal gear related to the outer sun gear.

The planetary gear support pin 2' is fixed to the planetary arm 3 for transmitting the revolution of the planetary gear 1' to the output side.
' is rotatably fitted to the outer circumferential surface of the planetary gear support pin 2', either directly or via a planetary gear bearing (for example, a needle bearing, a sliding bearing, etc.), with a minute gap maintained.

The planetary gear 1' meshes with a sun gear 5 provided at one end of the armature shaft 4a of the starter motor 4, and also meshes with an internal gear 6.
They interlock and rotate and revolve.

The internal gear 6 is supported by meshing with an external gear coupling 7a provided on a center bracket 7, and the center bracket 7 is fixed to a gear case 8.

When the components of the planetary gear reducer are assembled, the internal gear 6 and the plurality of planetary gears 1' are approximately located in the annular space 9 formed by the center bracket 7 and the armature-side center bracket 11. kept in a sealed state. This annular space 9
5. Fill the sun gear with grease. The meshing portions of the planetary gear 1' and the internal gear 6 are lubricated.

When the armature shaft 4a rotates, the plurality of planetary gears 1' revolve around the sun gear 5 while rotating on their own axis, and the revolution is outputted to the output side of the pinion shaft 10 via the planetary arm 3. Therefore, the planetary gear 1' receives meshing reaction forces from both the sun gear 5 and the internal gear 6, and the planetary gear support pin 2', which receives this load, is under extremely severe conditions.

Furthermore, the starter is often restarted by a switch, and at that time, the ring gear (not shown) fixed to the engine shaft and the pinion 10a are impactfully engaged, and the planetary gear support pin 2' is The load is several times greater, resulting in extremely harsh operating conditions.

However, lubrication between the planetary gear support pin 2' and the planetary gear bearing has been achieved by applying grease to the smooth outer circumferential surface of the planetary gear support pin 2' and the inner diameter surface of the bearing.

When the starter is started, since the outer peripheral surface of the planetary gear support pin 2' is smooth, grease is easily discharged from both ends to the outside due to centrifugal force, resulting in poor lubrication between the planetary gear bearing and the planetary gear support pin 2'. becomes. In addition, since the planetary gear support pin 2' is subjected to a high load, the oil film is easily broken, often resulting in a completely melted contact state, which may cause seizure or abnormal wear of the planetary gear support pin 2' and the planetary gear bearing, such as a needle bearing. occurs. As a result, the radial clearance between the planetary gear support pin 2' and the planetary gear bearing becomes excessive, vibration noise increases, and damage such as flaking occurs to the planetary gear bearing or the planetary gear support pin 2'. This caused the problem that the starter's function was impaired.

(Object of the Invention) The present invention has been made to solve the above-mentioned problems of the prior art. Baking with enough
The purpose is to provide a planetary gear reduction starter equipped with an excellent lubrication structure to prevent abnormal wear.

[Summary of the invention]

The planetary gear reduction type starter according to the present invention has a central sun gear provided on the armature shaft of the starter motor, an internal gear related to the outer sun gear, and a plurality of internal gears that mesh with each other to rotate and revolve. A planet comprising a plurality of planetary gears and a planetary arm for transmitting the revolution of the planetary gear to the output side, and the plurality of planetary gears are rotatably fitted to a planetary gear support pin fixed to the planetary arm. In the gear reduction type starter, at least one of the outer circumferential surface of the planetary gear support pin and the inner circumferential surface on the side of the planetary gear that fits therein,
A concavo-convex surface portion in which a lubricant is to be sealed is formed, and the concave-convex surface portion communicates with an arm hole communicating from an end surface of the planetary gear support pin to an outer circumferential surface of the planetary gear support pin.

Additionally, in the present invention, an uneven surface portion is formed on at least one of the outer circumferential surface of the planetary gear support pin 2 and the inner circumferential surface on the planetary gear side, so that grease can be sufficiently retained.

Further, the planetary gear support pin is provided with a through hole that communicates from the end surface to the outer circumferential surface, so that grease can be supplied to the sliding surface.

Since the surface of this uneven surface portion becomes a sliding surface, the protrusions are processed to be smooth and the recesses are used as oil pools.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 1 to 10.

FIG. 1 is a sectional view of a planetary gear portion of a planetary gear reduction type starter according to an embodiment of the present invention, FIG. 2 is a perspective view of a planetary gear support pin thereof, and FIG. 3 is an A of FIG. -A sectional view.

In this embodiment, a needle bearing 12 is used as a bearing for the planetary gear in a planetary gear reduction type starter having the same configuration as previously explained in FIG. 12.

That is, the planetary gear 1-, in which the needle bearing 12 is press-fitted, is rotatably fitted to the planetary gear support pin 2, which is fixed to the planetary arm 3 by press-fitting, with a minute gap maintained.

The planetary gear support pin 2 has a groove 13 forming an uneven surface portion on its outer peripheral surface 2a. This groove 13 is connected in the circumferential direction, and in the axial direction, a plurality of lateral grooves 13a having a length smaller than the width M of the roller 12a of the needle bearing 12 are formed.
is connected to

Note that the boss length of the planetary gear 1 is L. Groove 13°13a
The cross-sectional shape of the groove is rectangular, U-shaped, seven-shaped, etc., but the bottom of the groove is rounded to avoid corners to prevent a decrease in strength. Then, a horizontal hole 14 is made in the axial direction from the end 2b of the planetary gear support pin 2, and a plurality of vertical holes 15 are made from within the groove 13 on the outer circumferential surface 2a so that they penetrate through each other. In other words, the groove 13 of the uneven surface portion formed on the outer peripheral surface 2a of the planetary gear support pin 2 is formed on the end surface 2b of the planetary gear support pin 2.
It is configured to communicate from the armhole to the outer circumferential surface 2a of the planetary gear support pin 2.

Side hole related to this armhole 1.4. The vertical hole 15 is filled with grease as a lubricant in advance, and the sliding surface can be replenished little by little with centrifugal force during operation.

A more sufficient lubrication state can be obtained by cutting a thread at the end of the side hole 14 and capping it with a small screw to prevent the filled grease from scattering.

Since the load applied to the planetary gear support pin 2 is applied in a fixed direction during operation, it is necessary to dispose the planetary gear support pin 2 so that it is shifted in the circumferential direction so that the axial groove 13a does not coincide with the cargo shape direction.

According to this embodiment, a groove 13.13a for sealing grease is formed on the outer peripheral surface 2a of the planetary gear support pin 2,
In addition, by providing an armhole that communicates from the end surface 2b of the planetary gear support pin 2 to the outer circumferential surface 2a, grease retention is ensured, and the outer circumferential surface 2a of the planetary gear support pin 2 and the roller 12a of the needle bearing 12 related to the planetary gear side are separated. As the planetary gear 1 rotates, an oil film is formed on the sliding surface that fits with the inner circumferential surface, resulting in a good lubrication condition, preventing seizure, abnormal wear, flaking, etc. on the sliding surface, and preventing the planetary gear from seizing, abnormal wear, flaking, etc. The durability of the speed reduction starter can be improved.

In addition, in the case of a starter, the planetary gear reducer is not operated continuously, so the temperature near the planetary gear is appropriately heated and cooled, and the grease flows smoothly, so that it can be used for continuous operation. This results in better oil lubrication conditions than when

Next, another embodiment of the present invention will be described with reference to FIGS. 4 and 5.

4 is a side view of a planetary gear support portion of a planetary gear reduction type starter according to another embodiment of the present invention, and FIG. 5 is an enlarged cross-sectional view taken along line BB of part 0 in FIG. 4.

In the embodiment shown in FIGS. 4 and 5, the planet gear support pin 2 is directly connected to the planet gear IA without using a planet gear bearing on the planet gear side.
This is a case where A is slid, and the inner circumferential surface 1a of the planetary gear IA
A groove 17 is provided to form an uneven surface portion. In addition, in FIG. 4, only a part of the tooth portion of the planetary gear IA is shown, and the tooth bottom diameter is shown with a chain double-dashed line. In the figure, 1st. Second
Components with the same reference numerals are equivalent to those in the previous embodiment.

The cross-sectional shape of the groove 17 is the same as in the previous embodiment, such as rectangular, U-shaped, and 7-shaped. Further, the direction of the groove 17 can be an axial direction, a circumferential direction, or both directions orthogonal to each other.

FIG. 5 shows an example of a U-shaped cross-sectional shape and an axial groove.

The planetary gear support pin 2A has a horizontal hole 14 and a plurality of vertical holes 15 that communicate from its end to the outer circumferential surface 2a, that is, the sliding surface, and the through holes are filled with grease 16.

Similar to the planetary gear reduction type starter shown in FIG. 12, when the armature shaft 4 rotates, the planetary gear IA revolves around the planetary gear support pin 2A while rotating.

In the planetary gear reduction type starter, the direction of the load applied to the planetary gear support pin 2A is constant, but the direction in which centrifugal force acts constantly changes as the planetary arm 3 rotates. At the rotational position where the direction of the centrifugal force matches the direction of the vertical hole 15, the grease 16 is pushed out to the sliding surface with the greatest force. The gear support pin 2'A is fixed to the planetary arm 3.

At that time, the direction Y of the force acting on the planetary gear support pin 2A
Since it forms approximately 90 degrees with the centrifugal force direction X, it is necessary to ensure that the direction of the vertical hole 15 does not coincide with that direction. If the vertical hole 15 coincides with the direction of the force acting on the planetary gear support pin 2A, the area that receives the load will be reduced, and there is a possibility that the surface pressure strength of the contact surface will be reduced. The axial length of the groove 17 is made smaller than the boss length L of the planetary gear IA so that the grease 16 does not flow out in the axial direction.

According to this embodiment, by forming a groove 17 for sealing grease in the inner circumferential surface 1a of the planetary gear IA, and by providing a through hole leading from the end surface of the planetary gear support pin 2A to the outer circumferential surface 2a, The same effects as in the previous embodiment are expected.

In particular, the grease 16 pushed out from the vertical hole 15 of the planetary gear support pin 2A by centrifugal force is transferred to the inner circumferential surface 1a of the planetary gear IA.
The rotation of the planetary gear IA forms an oil film on both sliding surfaces, thereby maintaining a good lubrication state. Furthermore, even if wear particles enter between the planetary gear IA and the planetary gear support pin 2A, the wear particles accumulate at the bottom of the groove 17 formed on the planetary gear inner peripheral surface 1a due to centrifugal force, and the sliding surface is clean and prevents seizure, abnormal wear, etc.

Next, still another embodiment of the present invention will be described with reference to FIGS. 6 to 8.

FIG. 6 is a sectional view of a planetary gear portion of a planetary gear reduction type starter according to still another embodiment of the present invention, FIG. 7 is a developed view of the inner circumferential surface of the planetary gear in FIG. 6, and FIG. , D-D in Figure 7
FIG. In the figure, parts with the same reference numerals as those in FIGS. 1 and 2 are equivalent parts, and therefore the explanation thereof will be omitted.

In this embodiment, similarly to the embodiments shown in FIGS. 4 and 5, the uneven surface portion for sealing grease is formed on the inner circumferential surface 1a of the planetary gear IB.
However, the grooves 18 forming the uneven surface portion are arranged in a grid pattern.

The cross-sectional shape of the groove 18 may be a U-shape, a 7-shape as shown in FIG. 8, or a rectangular shape (not shown).

Since the groove direction of the groove 18 is formed at 45 degrees with respect to the rotation direction, the grease flows easily and the planetary gear IB and the planetary gear support pin 2B are well lubricated.

A horizontal hole 14 which is a through hole leading from the end surface of the planetary gear support pin 2B to the sliding surface. Since a plurality of vertical holes 15 are provided and the grooves 18 communicate with the uneven surface arranged in a lattice pattern, an even better lubrication state can be ensured by filling the through holes with grease.

In addition, effects similar to those described in the embodiments shown in FIGS. 4 and 5 can be expected.

Next, FIG. 9 is a perspective view of a planetary gear support pin showing still another embodiment of the present invention, in which the same reference numerals as those in FIG. Therefore, its explanation will be omitted.

The planetary gear support pin 2C shown in FIG. 9 has a circumferential groove 13 similar to that in FIGS. 1 and 2 on its outer peripheral surface, and further has grooves 13b formed in both directions at 45 degrees with the axial direction. It is.

According to the embodiment shown in FIG. 9, exactly the same effects as those of the embodiment shown in FIGS. 1 and 2 can be expected.

FIG. 10 is a perspective view of a planetary gear support pin showing still another embodiment of the present invention, and FIG. 11 is a sectional view taken along line E-E in FIG. 10, in which the same reference numerals as in FIG. Since this is the same part as the embodiment shown in FIGS. 1 and 2, the explanation thereof will be omitted.

The uneven surface portion formed on the outer circumferential surface of the planetary gear support pin 2D shown in FIG.
9 formed in high density.

The cross-sectional shape of the groove may be any shape such as a U-shape as shown in FIG. 11, a square square shape (not shown), or a rectangular shape.

Since the outer peripheral surface becomes a sliding surface, the surface is finished after knurling so that the protrusions on the surface are smooth. The knurling width Q is made narrower than the boss length of the planetary gear, as in the previous embodiment.

According to the embodiment shown in FIG. 10, the same effects as those explained in the embodiments shown in FIGS. side hole 14. The grease filled in the vertical hole 15 constantly forms an oil film on the sliding surface, ensuring a good lubrication state.

Note that each of the above-mentioned embodiments can expand the scope of application.

For example, in the embodiments shown in FIGS. 1 and 2, the needle bearing 12 is used as the planetary gear bearing, but the same applies to the case where a ball bearing or a roller bearing is used instead of the needle bearing.

In addition, in the embodiments shown in FIGS. 4 to 8, when the outer circumferential surface of the planetary gear support pin and the inner circumferential surface of the planetary gear are directly sliding surfaces, an uneven surface portion is formed on the inner circumferential surface of the planetary gear. However, for example, the axial groove 17 (Fig. 5) or the lattice groove 1
An uneven surface such as 8 (FIG. 7) may be formed on the outer peripheral surface of the planetary gear support pin.

Furthermore, in the embodiment shown in FIG. 10, the knurled groove 19 formed on the outer circumferential surface of the planetary gear support pin 2D can also be formed on the inner circumferential surface of the planetary gear. In this case, centrifugal force makes it easier to retain the grease, resulting in better lubrication.

In all of the above embodiments, each side forming an uneven surface, that is, each groove on the inner circumferential surface of the planetary gear, is particularly illustrated and explained when a sliding bearing is press-fitted into the planetary gear and used as the planetary gear side. Although this is not the case, similar functions and effects can be obtained by forming similar uneven surfaces, that is, grooves, on the inner circumferential surface of the sliding bearing.

〔Effect of the invention〕

As described above, according to the present invention, lubricating oil is sufficiently retained on the sliding surface between the outer circumferential surface of the planetary gear support pin and the inner circumferential surface on the planetary gear side, thereby preventing the occurrence of seizure, abnormal wear, etc. A planetary gear reduction starter with an excellent lubrication structure can be provided.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a planetary gear portion of a planetary gear reduction type starter according to an embodiment of the present invention, FIG. 2 is a perspective view of a planetary gear support pin thereof, and FIG. 3 is an A of FIG. -A sectional view, FIG. 4 is a side view of a planetary gear support portion of a planetary gear reduction type starter according to another embodiment of the present invention, and FIG.
FIG. 6 is a cross-sectional view of a planetary gear portion of a planetary gear reduction type starter according to still another embodiment of the present invention, and FIG. 7 is an enlarged cross-sectional view of the planetary gear portion shown in FIG. 8 is a sectional view taken along the line DD in FIG. 7, FIGS. 9 and 10 are perspective views of a planetary gear support pin showing still another embodiment of the present invention, and FIG. is a sectional view taken along line E-E in Figure 10.
FIG. 2 is a front sectional view of a general planetary gear reduction type starter. 1, IA, IB... Planetary gear, 1a... Inner peripheral surface, 2
゜2A, 2B, 2C, 2D... Planetary gear support pin,
2a...outer peripheral surface, 2b...end face, 3...planetary arm,
4... Starter motor, 4a... Armature shaft, 5...
・Sun gear, 6... Internal gear, 1-0... Pinion shaft, 12... Needle bearing, 13, 13 a
, 13 b-groove, 14...horizontal hole, 15...vertical hole, 16...grease, 17°18...groove, 19...
・Fine grooves. 1 figure, 3 figures, 4 figures, 5 figures.

Claims (1)

[Scope of Claims] 1. A central sun gear provided on the armature shaft of the starter motor, an internal gear related to the outer sun gear, and a plurality of planetary gears that mesh with these gears to rotate and revolve. and a planetary arm for transmitting the revolution of the planetary gear to the output side, and the plurality of planetary gears are rotatably fitted to a planetary gear support pin fixed to the planetary arm. In this method, an uneven surface portion in which a lubricant is to be sealed is formed on at least one of the outer circumferential surface of the planetary gear support pin and the inner circumferential surface on the side of the planetary gear that fits therein, and the uneven surface portion The planetary gear reduction type starter is characterized in that the end face of the planetary gear support pin is configured to communicate with an oil hole communicating with the outer peripheral surface of the planetary gear support pin. 2. In the item described in claim 1, the uneven surface portion is formed by a plurality of grooves that form a lubricating oil film on the fitting surface between the outer circumferential surface of the planetary gear support pin and the inner circumferential surface on the planetary gear side. It is a planetary gear reduction type starter. 3. A planetary gear reduction type starter according to any one of claims 1 and 2, wherein the uneven surface portion is formed of grooves formed in a lattice shape. 4. A planetary gear reduction type starter according to any one of claims 1 and 2, wherein the uneven surface portion is formed by knurled fine grooves.